Alternator or ground short to chassis.

Only way hand brake light can come on, is if there is a major backfeed of power.

I would take the back board off of the gas tank and look at the tank.

You could just unplug the charge wire off of the back of the Alt. That would tell you alot when you started it again.

Might want to Ohm all of the fuses again. My bet is you popped one or two. Better take the K-40 apart and look at it too. Before its too late.

 

Thanks MM!

Il check all the fuses again tomorow. also will check the grounding wires behind the cluster itself. (From what I have read from searching this forum)

Where is the K-40 located on the W202?

Il also check out the alternator. You say disconnect the "charge wire?"

 

Picture sent to your phone.

 

Thanks again MM..

I did reply, maybe u did not receive it..

Is that relay located in the trunk? On the right hand side next to the spare wheel and battery? I think that's where I seen this relay..

Daylight has arrived. So I can go investigate this matter further..

Thanks for the pointers..

Any other things I can check while I'm at it?

 

Is that relay located in the trunk?

No its under the hood in the same area as the BASE is, in your 140.

 

Ok thanks my friend

Will report back with my findings

 

I got the chat open over there. be there for a few hours, look me up.


I getting another pic for you too hold on.

 

Check all these terminals, not just the ones with arrows, but all.


What your looking for is dis-coloration of the metal on the terminals.

And if any of the wiring does not come out when you release the clips, it might be because it melted the plastic around the terminal area, making it stick.

 

Unfortunately I'm using my fone, so I won't be able to log on that side for now.. (Chat does not work on mobile)

So I've looked all over, checked all the ground wires, everything was fine..

Checked the cluster (just in case) and it too was flawless, no burnt resistors..

Just still can't find this k-40 relay!!! Lol, looked all over! Do u have a pic of where it locate on a W202?

 

Could a faulty speed sensor cause this?

Also I replaced the temp sensor this morning, still no temp reading on the cluster

 

Go back and read post #8 again.

 

I looked everywhere!!! Believe me its not there my friend.. (I tried to upload a pic of that area, but my Blackberry keeps crashing)

Is it possible that the K-40 was combined with the LH module? I just stumbled across something interesting, probably the root cause..

My LH module part numbers are:
202 545 44 32
It also has the letters K-40 printed on the side with the part number..

Now when I scan it with my Carsoft 7.4 this is what comes up:

Single Dianosis LH - Staus Error

Module info: LH
MB - Nr: 022 =34 12 38
Supplier: Bosch
Hardware version: 56/52
Software version: 10/30
Diagnosis recogn: 00/11
Engine size: 0,7l
Program version: 05
Data version: 04

Lh_feh.dxt

17 Fault in CAN communication with EFP control unit

While IGNITION OFF, unplug coupling at EFP control unit and test with ohmmeter directly at coupling. Resistance = 115-125 ohm. Or EZL ignition control unit is not transmitting.


3 Coolant temp sensor: sensor circuit 2 open circuit / short circuit.

Verify coolant temp sensor voltage at sensor circuit 2.
20'c = 3,5v =2500 ohm.

- single diagnosis completed.




Noiw before we even look at the errors, what draws my attention is the incorrect information about the module itself..

The "MB number" or part number is totaly wrong and even contains a "="

It says the engine size is "0,7l"????

And the hardware / software versions don't seem correct..

So what do you think mm? My LH module on this car is kaput? I'm almost sure that this is the culprit, because on all my other scans I have never seen this before..

The module build date is 28 / 11 / 1995.. So I guess they interchangeable without needing re-programming?

If you concur with my thoughts about this, I can quickly take a ride to my local breakers and pick a replacement module for about $50 if they have the right one. (I'm quite sure they do)

What's your thoughts on this?

 

My 10 cents, change the LH control unit.

 

**UPDATE**

Ok so today I went ahead got a replacement module.. Cost me bit more than I thought, but if it fixed the probs it would be worth it.

Disconnected the battery, unplugged the old "faulty" module and replaced it with a module from a really low milage donor vehicle..

Reconnected everything properly, and went to start the car.

Started up perfectly (as it did before) BUT.. The cluster issue was still there!!!! Speedo not working, fuel gauge misleading and temp gauge not working..

Car drives fine though.

I wanted to hook the Carsoft up to the car again just to erase any errors and verify that the module is connecting to the car properly.

Started to rain, and rain hard.. Will have to perform further tests tomorow during the day, if the rains don't prevent the progress..

Upon initial tests, the problem is there.. So far I tried replacing:

- Instrument cluster
- LH computer module (part number 202 545 44 32)

Also I checked all the ground cables and connections which all seemed solid.

Mercedes Mechanic, did u get a pic of where the K-40 relay is located on a W202? I looked hard at the breakers and could not find that part maybe it is in deed a major culprit in this case?

Pics to come later..

 

Mercedes Mechanic, did u get a pic of where the K-40 relay is located on a W202? I looked hard at the breakers and could not find that part

It has a OVR not a k-40, I didnt look at the year.

 

its understandable...

So where do I go from here? What's the next place I should look to solve this prob?

Cluster - fine
LH computer module - fine


Could it really be the invidual sensors? Speed sensor, fuel level and temp sensor?

I disproved that theory by replacing the temp sensor and still no reflection on the gauge.

So I'm left standing just scratching my head lol.. Still gotta do that diag and memory erase tomorow, but after that I have no plan yet to go forward and solve this issue..

What's the next step?

 

So I'm left standing just scratching my head lol.. Still gotta do that diag and memory erase tomorow, but after that I have no plan yet to go forward and solve this issue..

What's the next step?

On the fuel gauge issue, did you check to make sure your tank is not caved in?




I KNOW YOU checked all the connectors. I would say that the temp guage is caused by faulty wiring, but let me go check the diagrams.

Be right back.

 

Yes I did check all the connectors.. Everything was clean as new..

Its not just the temp gauge that's still not working.. Speedo don't work, and it throws up many of the warning lights on the dash. Handbrake light, Aswell as the window washer fluid light, even though the tank is full of water..

Intermittently, the speedo would work and all the warning lights go off.. Once the speedo dies all the warning lights return..

I have never seen the temp gauge go up since I go the car..

In regards to the fuel tank, where do I find it? Under the car like other normal vehicles? Have never tampered with a fuel tank before..

 

Mafia, I am almost sure its an alternator problem, it really smells like it.

Ok, do this for the fuel guage.

1. Remove instrument cluster and check voltage at connector 2 between pin 4 (Blue/White wire) and pin 5 (Brown/Green wire). 0 volts at maximum fuel level and 8 volts at minimum fuel level.

2. Disconnect connector at fuel level senders and compare resistance of senders to each other. Each sensor should read similar resistance.
4 ohms at empty
25 ohms at 1/4
50 ohms at 1/2
75 ohms at 3/4
95 ohms at full

3. Inspect wiring at senders and measure resistance of corresponding wires from level senders to instrument cluster connector.

And...

1. Test resistance of each fuel level sender between the terminals. It should read approximately:

Resistance value = level indication.

8 ohms = 0
24 ohms = Reserve
51 ohms = 1/4
100.5 ohms = 1/2
145.5 ohms = 3/4
189 ohms = Full


Make it easy for you, if the tank is not caved in, one of the sending units will be bad.



On the temp guage, I would say skip it for now, if its not overheating, but here is the diagrams.


If you want my honest opinion, I think the mechanicals of the temp guage have gone bad (in the dashboard), the wiring is ok, so is the sensor(s).

 

Thank you MM..

I'll definately look into it more once the sun is up..

Getting quite tired of taking the cluster in and out of its place..

I have reached my spending limit on this car anyway, so if I can't get to the root of this problem, I'll just have to knock $150 off my asking price when I sell the car..

Let's hope we can get to the bottom of this issue before this car hits the market..

Re-sale value much better when everything works lol

 

Let's hope we can get to the bottom of this issue before this car hits the market.

I will help in the way I can.

 

Lol, no wonder you couldnt find it, some joker assembled your car backwards. The steering wheel is on the wrong side.

 

lol, not again with those RHD vs LHD jokes lol..

Right is "right" and left is "wrong"... I thought everybody knew that by now

 

Please take this to P.M. (I will be right there)

 

I just looked at the wiring diagram and if I have the correct year then this car has a drivers side SAM and everything for the instrument cluster goes through this unit N10/1 and it should be located in the rear of the fuse box. Can you take a pic of your fuse box.

 

I think you are on the money right there comrade eric!

I will have to take a pic of the rear of the fusebox in the day, will upload it asap..

In the meantime, do you have a pic of this N10/1 unit? Is it a relay? That little blue one? Lol..

I am really intrigued, and to obtain a replacement will be super simple for me!! Please any more info + pics you may have about this it might just save me a lot of hassel. Because I was contemplating the rear speed sensor to check next..

During the diagnostic on the HFM/PMS module, I did get a error "SAM failed to communicate with EFP" not sure if its related. But I erased that error.. Will see if it returns.


Funny story.. Had the engine washed on this car, then it started to idle funny and misfire.. Did a diag and Carsoft told me that the Coil which fires cylinder 2 and 5 was faulty.. I stripped everything out and found a ton of water in the holes where the spark plugs sit. Painstakingly removed all the water from each port and cleaned all the plugs to / from the coils.. Now the car driving great again!

Just have to solve these last few glitches anybody have pics of this N10/1 unit?

 

Anyone have a pic or more info on this N10/1 unit???

I just remembered I got a whole coffee jar full of relays for the C-Class.. Might even have a replacement without even needing to go anywhere..

Please comrades.. I'm patiantly waiting

 

I need your vin #

 

Here is the VIN:

Wdb2020286f360080


Thanx eric!

 

Damn N10/1 was fitted to the 202 as of 1.6.97 so sorry it is back to basics. Start by checking every ground wire for good contact.

 

1. Test for voltage supply and for good fuses under hood at fuse #1 with key on and fuse #10 at all times.

2. Remove combination relay N10 from fuse box. Test for voltage at Pin #8 with key on. Press hazard switch and verify voltage does not go away. If voltage supply is not found at pin #8 then the hazard switch may be at fault.

3. With voltage to pin #8 place a fused jumper wire between pin #8 and pin #10. Operate turn signal switch, the lights operated should stay on. Press hazard switch, all turn signal lights should stay on. If lights operate correctly, the combination relay may be at fault. If lights do not operate, retest for faulty hazard switch not being able to carry a load.





Its spot "D" in the fuse/relay box.

 

The car got sold today, so this problem will remain a mystery lol..

I got the temp gauge working at least.. SO the only two issues on that car were the speedo was scarcely intermittent, and the fuel gauge was misleading.. Never got around to sorting those issues out due to time constraints, but I got my full asking price regardless of these two minor issues. The rest of the car was excellent! The new owner was aware of these two small issues when buying the car, so everybody was happy.

Heres some pics of the car in question..

Thanks for every bodies help!!

 

The car got sold today, so this problem will remain a mystery lol..

Glad to hear.

 

Thanks for all your help MM..

Since the C280 is gone. Decided to fix up the C220 Classic abit more since its not selling as fast.

Bought a boot spoiler for it, damn thing cost me $70 still gotta get it painted, but that's not a prob.. Aligned the tail light abit better and changed gear leather boot.

Tomorow getting the interior properly cleaned, and taking a fresh set of pics before I re list it..

Things are going good so far